Potential starter for alternating-current motors.



H. W. CHENEY.

POTENTIAL STARTER FOR ALTERNATING CURRENT MOTORS.

APPLICATION FILED my? 1905 1,125,904; Patented Jan. 12, 1915.

2 SHEETSSHEET 1.

In Ven Zor- W511 sses Herbert Wlfheney H. W. CHENEY; POTENTIAL STARTER FOE ALTBRNATING CURRENT MOTORS. APPLICATION FILED JUNE'I, 1905. 1,125,004 Patented Jan.12,1915.

2 SHEETSSHEET 2.

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[n Ven [or Henber? W. (/2 en 65 AZZorney emanates seasonaronamsnnarrnse Specification of Letters laten't.

A .licetioa filed Junc- T. 1905.

To all whom it may concern:

Be it known that I. Rancher W. German a citizen of the ated States, residing at Norwood. in the county of Hamilton and State oi. '(ihio, have invented certain new and nseiul Improvements in l otezitial Starters for Alternating-Cmrent Motors. oi whichthe following is a toll. clfar, and act specification.

My present invention relates to starting devices for alternating current motors and more particularly to devices for starting polyphase inotors ofthe induction'type by varyint, the potential impressed upon the priinary winding of the motor.

The object of the invention simplify the construction and a angement of a potential starter and to produce one which is eflicient and er e in its peration and which, without change in its construction andwithout the substitution of parts. is adapted for use in connection with two phase and threephase systems of distribution.

The invention therefore consists of improvements in a system of control for al ternating current motors, and also improvements in the construction and arrangement of parts of a potential starter which will be hereinafter described and more particularly pointed out in the appended claims.

In the accompanying drawings. which illustrate the preferred embodiment of my invention, Figure 1 is a longzitudiinzl sectional elevation of the potential starter on the line 1-1 of Fig. 2; Fig tion of same on line i2--2, Fig. 1; Fig. 3 is an exterior View orta slightly modified. form of the starter in side elevation; Fig. i is an 'exteriorriew of the starter of Figs. 1 and 2 in front elevation; Fig. 5 is a diagrammatic representation of my improved potential starter, used in connection with a threephase system; Figs. 6 and 7 are diagrams of the connections made by the starter in Fig. 5 in the starting and running positions, re-

Spectively; Fig. 8 is a diagrammatic reprei sentation of the-starter used in connection with a two-phase system; and Figs. 9 and 10 are diagrams of the connections made by the starter in Sin the starting and running posit-ions respectively.

Referring to Figs. 1 .to 4 inclusive, the two single coil transformers l2 and. 12 each is a sectional eleva-v l 'GHIO, ASSIGNOR, BY TEESNE ASSXGNMENTS, T9 I ENG COMPANY, e1 GQJJ'BGEATION 0F IJELAVIA'ELE.

' e'snr Morons.

'4 w 1 r Batches-d Jan. 12.

Serial No. 2.8%,162.

consist of the windings 13 and cores l t nitmnted in no 15. T he windings of the two trarstorniers l2 and 12 when connected for a three-phase system, may be considered together as forming V-connected autotransformer windings. This frame 15 is supported on the bolts l6 fastened to the bracket 11. which also carries the casing cover 1?. Suspended from said bracket is a controlling switch B. This switch comprises the contact lingers a and the drum 2.0

ca rrvingz; the contact sernnents The drum '20 i' cot'atably mounted on a stationary stud or spindle '20 held rigidly in the ends of the downwardly projecting lugs and 2% respectively. These lugs may be integral y th or etherwise fastened to the bracket 11. Mounted upon the insulating blocks 26 also suswiu i from said bracket are the contact ti gcrs a. which are adapted to co-act with "the contact segments in a manner to be hereinafter described. These contact lin- Qcrs are connected with the motor terminals and transformer terminals and taps from said trmisforrners by the leads (Z, only part of which are shown in Figs. 1 and 2, the most of said leads bring omitted for the sake of clearness of illustration. Some of these leads are directly connected to the transformer windings within the casing and some pass out of the casing through insulati'ng bushings in openings formed at 27 in the sides of the bracket 11, (as shown in ins. 1.2, and 4..)

In the modification shown in Fig. 3 the leads pass out of said casing through the rear of bracket 11 (as shown at 28 in Fig. 3.)

Mounted upon the drum 20 is a gearwheel which meshes with an idler gear 30 which in turn meshes with the gear .31 mounted upon the horizontally projecting shaft in bracket 11. Tlie shaft is provided with the double operating handle 33 carrying the index lingers ir, which point to the projections 37 3(3, and 37 on the face of bracket ll, indicating respectively the oft, starting, and running positions (Xl the controlling switch.

to the starting position when the motor is running at its proper speed, I provide mechanism for constraining the operating shaft to move always in OIlSdll'eCtlOIi 1n operating the potential star er from the runinclusive, the starter is shown in its of? brings the drum into the ning position. This mechanism comprises the ratchet wheel 38 mounted upon shaft 32 having cooperating therewith the spring-pressed pawl 39. As here shown some of the teeth upon said ratchet wheel 38, namely, teeth 38 which correspond to the off and running positions, are so constructed that the operating shaft is constrained to move in a clock-wise direction when leaving the oii and running positions. The remaining teeth 38*, correspending to the starting positio'n are so arranged as to permit the drum to be moved freely in either direction from the starting positions. It is sometimes desirable to return immediately to the oii osition from the f starting position, In *igs. 1 to 4 position, the operating handle being horizontal. As the handle ismoved'in a. clock wise direction and the index iingers 34 point to the projections 36, the druriiQQ is moved into the starting position. A further movement in the same direction, until the index fingers point to projections 37 running position. A further movement in the same direction brings the handle again into the horizontal position and the drum 20 into its of? osition, 180 removed from its initial position. A further movement of 180 in the same direction will move the drum again through starting and gum ning positions and said drum will be returned to its initial-off position. To'accomplish this controlling operation by 180 movement of the drum and operating handie, I mount the contact fingers on both sides of the horizontally arranged drum and arrange the contact segments on oppo- -te sides of said drum in exact duplicate. The controlling drum and contact fingers are preterably arranged to operate in an oil bath and for-"this purpose the oil tank 40 is provided. This tank contains oil preien ably up to the'level all and the drum is completely immersed in the oil. The tank is suspended from bracket 11 by any desirable means, preferably by the pivoted boltsdZ as snown in F1gs. 2, 3, and 4. I

By referrlng to Figs. 5 and 8, it will be seen that the controller drum (here shown in development) is provided with two duplicate sets of straight bridging contact segments 6 b b and 6*, the segments 5 and t of each set corresponding to the starting position indicated by the vertical lines 5 and the segments 5 and b of each set correspond1ng to the running position indicated by lines R. These segments co operate with the contact fingers an to a inelusive in various operative positions of the controlling switch. The controlling switch in Fig. 5 is arranged to connect the transformers 12 and 12 and the three-phase motor M to the mains f, g, and k of a threephuse system of distribution. The controlling switch in Fig. 8 is arranged to connect the transformers 12 and 12* and the twophase motor M to the mains 7s, m, n, and p of a two-phase system of distribution. In either case the transformers 12 and 12 are the some and tops are brought off at the intermediate points 45 and 45. The controller drums and fingers are also the same in each case. The only thing necessary to adapt my improved starter to a three-phase or a two-phase system is to change the leads at, a few of the contact fingersas may be clearly seen by an inspection of Figs. 5 and 8. The finger a is not employed in the three-phase connections.

When the controlling switch shown in Fig. 5 is moved into its starting position S, the segments 6 and b of one set are in engagement with the fingers a, a a a, and c" and the corresponding segments of the other set are in engagement with the fingers a, a a, and a. This results in the connections clearly shown in Fig. 6, the transformer coils being V connected, or connected in open delta across the threephase mains f, g, and h, and the motor M connecmd between the taps &5 and i5 and the main it to which both transformer coils are connected. A potential lower than the potential of the mains is thus impressed upon the primary windings of the motor and same starts with considerable torque and a reduced flow of current in the secondary windings. When the controlling switch is moved into the running position R, the seg ments Z5 and 6* of one set are in engagement with fingers a a a, and a. and the segment 5 of the other set is in engagement with the contact fingers a and a, giving the connections shown in Fig. 7. In this running position the transformer coils'are completely out out of circuit and the motor M is directly connected to the mains 7, g, and k, thereby impressing the full potential of the mains updn the motor primary winding-and increasing the speed of the motor. In passing to this position,

- the protective devices, or fuses m and y are 1 winding being connected between tsp and one end. of transformer 12, the

phase of the motor being connected bSlT'JQ the tap 45 and one end of the transformer 12. former coils are cut ou u of circuit and the 1-1 modifications of my invention whic- V 15L ters Patent is the In the running position the trans scope.

' Having thus described my lIlVGlltlOil, what I cla m as new and desire to secure by Let- 1. In a potential starter, a-braclaet, transformers mount-ed uponsaid bracket, a con trolling switch comprisin a contact carry ing drum and co-acting contact fingers supported by said bracket, a tank containing; oil in which said controlling switch is immersed, a controlling handle geared to said 'drum, and ratchet and pawl mechanism for "constraining said handle to move always "the same direction from certain positions of trollin switch com rising a lonsitndi acting contact fingers suspended from said said drum,

2. In. a potential starter, a bracket, tran fo'rmers mounted upon said bracket, a con- Elli:

mounted contact carrying drum bracket at opposite sides of the drum, on

tank containing oil in which said. and s'aid contact fingers are immersed, mg shaft projectlng horizontally an operatfroin bracket, a handle carried by said shaft, and gearing between said shaft and lit 1 3. In a potential starter, a ,ket, trans formersniounted upon said bracket, a con trolling switch comprising a contact carrying drum and co-acting Contact fingers suspended from said bracket, a controlling handle geared to said drum, rotclict pawl mechanism for constraining said l endle to move always in the same direction from certain positions of same, and a suspended from said brsclze t and cont oil in which said drum imm rsed, the shaft of said handle being above the level of the oil.

4;. In a potential starter, a bracket, "ransformers mounted upon said bracket, s controlling switch comprising a contact carry ing drum and coacting contact lingers suspended from said bracket, a tank containing oil in which said controlling switch is inimersed, an operating geared to said drum, and ratchei and pawl mechanism for constraining said o ierating shaft to more always in a forward direction from certs-m1 of the operative posit ons of the controlling switch.

5. In a potential starter, a bracket, formers mounted upon said bracket, a conmeme-e trolling switch comprising" a contact cerrying drum and co-acting lingers suspended from said bracket, a tank containing oil in which said controller is immersed, controlling handle geared 'to said drum, and ratchet and pawl mechanism for constraining said handle to move always in the same direction from certain operative positions while permitting said handle to move in either direction from other positions, the contacts of said controlling switch and the operating mechanism tl'iere'for being so arrnn that the handle is moved forward through l8? the controlling switch passes :uccessiwl r into the starting, running,

of? positions.

ooten al starter, a controlling th a pie. lit-y of pairs of c sets of straight bridging contact segments, and two sets of contact lingers 1 either of which sets of fingers anyset seid hridging contactsegments rosy be made to cooperate,

7. in a potenti drum provided with l duplicate sets or traight .0 sets or 5 and sets of 4 sition, end

ins its 0 2 L 1, or consecrlike? 8. combination, a su dnction motor. entocentre- ,i'erci i, positio connecting the in supply c1icnit tliro "n the auto-tron sfornier windings, conncc motor to ,the supply circuit directli? enddisconn cting the motor, means 501' n, a supply circuit, innier windings, a

on direction and positions for connecting the inotor to the 1 circuit auto transformer win-hugs, i'or 1g the motor to the supply circuit directly, and for dlSCQllll\ e the motor. and means preventing the controller n 'g'iassing from Lions directly to the cote :ows of g co n acts, and lTlOlLlilG to bring mine: he of starting or running contacts into s1 aneous engagement with said sets {ll 231C act fingers,

. W, J3 .4. L. any row or chi-nieces usin an starter, a controlling contact segments 5 and o in ber, of means for permitting motion of said member in one direction only from the ofl' and running positions while permitting either backward or forward movement from starting position.

13. In a potential starter, the combination of a controlling drum provided with a plurality of sets of counterpart groups of straight bridging contact segments and a plurality of groups of contact fingers with any one of which groups of fingers any group of said bridging contact segments may be" made to cooperate. V

'14:. In a controller, the combination with a plurality of sets of contact fingers, of a rotatable drum having a plurality of counterpart rows of starting contacts and a plurality of counterpart rows of running contacts, said drum being movable to bring any row of contacts into engagement with any set of contact fingers, the different rows of starting contacts or of running contacts all engaging the respective sets of contact fingers simultaneously.

15. In a potential starter, the combination of a plurality of sets of contact fingers, a controlling drum provided with a plurality of counterpart sets of bridging contact segments, said drum being movable to make any set of contact segments cooperate with any set of contact fingers, and each set of contact segments being arranged to cooperate with sets of contact fingersin a plurality of positions in each of which each bridging contact segment extends in a straight line between all the fingers it bridges.

16. In a controller, the combination of a bracket, a controlling switch con prising a contactcarrying drum and coacting contact fingers suspended from said bracket, a tank containing oil in which-said drum is in mersed, a controlling handle geared to said drum, and ratchet and pawl mechanism for constraining said handle to move always in the same direction from certain positions of said drum.

17. In a controller, the combination of a bracket, a controlling switch comprising a longitudinally mounted contactcarrying drum and co-acting contact fingers suspended from said bracket, the fingers being'at diametrically opposite sides of the drum, an oil tank'containing oilin which said drum and contact fingers are immersed, an operating shaft projecting horizontally from the bracketabove the surface of the oil, a handle carried by said shaft, and gearing between said, shaft and drum.

13. In a controller, the combination of a tank containing oil, a controller drum immersed in the'oil in said tank, the shaft of said drum being substantially horizontal, contact fingers cooperating with said drum, an operating shaft substantially parallel to the shaft of the drum and above the surface of the oil in said tank, and gearing between said two shafts.

19 In a controller, the combination of a tank containing oil, a controller'drum immersed in the oil in said tank, the shaft of said drum being substantially horizontal, sets 1 f contact fingers diametrically opposite eaclother and cooperating with said controll r drunnan operating shaft, a handle von said shaft above the level of'the oil in said tank, and gearing between said operating shaft and the shaft of the controller drum.

In testimony whereof I ailix my signature, in the presence of two witnesses.

HERBERT onnnm' Witnesses LAURENT LOWENBERG, FRED J. KINsnY. 

